The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Cyrille A Dhaese - One of the best experts on this subject based on the ideXlab platform.

  • a new species and first record of the genus triacanthella schaffer 1897 collembola poduromorpha Hypogastruridae for africa
    ZooKeys, 2012
    Co-Authors: Charlene Janion, Cyrille A Dhaese, Louis Deharveng
    Abstract:

    CITATION: Janion, C., D'Haese C. A. & Deharveng, L. 2012. A new species and first record of the genus Triacanthella Schaffer, 1897 (Collembola, Poduromorpha, Hypogastruridae) for Africa. ZooKeys, 163:57–68, doi: 10.3897/zookeys.163.2298.

  • an ancient antarctic endemic genus restored morphological and molecular support for gomphiocephalus hodgsoni collembola Hypogastruridae
    Systematic Entomology, 2011
    Co-Authors: Penelope Greenslade, Mark I Stevens, Giulia Torricelli, Cyrille A Dhaese
    Abstract:

    Gomphiocephalus hodgsoni Carpenter was only the second collembolon† to be described from the Antarctic continent. It was collected first in 1902 from Granite Harbour, southern Victoria Land, Eastern Antarctica, by the British National Antarctic Expedition (1901–1904). Since then several studies have investigated the distribution, ecology, ecophysiology and molecular composition of the species. Despite two morphological redescriptions and an absence of detailed evolutionary phylogenetic studies, the genus Gomphiocephalus was recently reduced to a subgenus of Schoettella Schaffer. Here, we redescribe the species in detail and use morphological and molecular (cytochrome c oxidase subunit I and 28S) data to indicate its generic relationships within Hypogastruridae. Characters of Gomphiocephalus do not conform with those of any extant genus in the family, including Schoettella. In addition, the only Schoettella species described from the southern hemisphere, Schoettella subcorta Salmon, is shown here to belong in the genus Xenylla. Furthermore, molecular data indicates the genus has no close relationship to any other in Poduromorpha, and in particular Hypogastruridae. Therefore, we restore Gomphiocephalus to generic status. Our results reinforce the already recognized high level of endemism in the Antarctic fauna at both species and generic levels, and emphasise the necessity of using both morphological and molecular data in determining the systematics and evolutionary relationships of the fauna.

  • is psammophily an evolutionary dead end a phylogenetic test in the genus willemia collembola Hypogastruridae
    Cladistics, 2000
    Co-Authors: Cyrille A Dhaese
    Abstract:

    The law of the unspecialized states that specialized taxa have evolved from more generalized ancestors. Moreover, it is usually assumed that ecological specialization is irreversible and hence leads to extinction. This study aims to test these assumptions using a phylogenetic framework in a case study within the springtail genus Willemia and its diverse life habits. This genus is represented mostly by loam-dwelling species (generalized condition), but some species are psammophilous, living in sandy habitats (specialized condition). Fifty-two morphological characters were examined in 34 of the 36 species of the genus and in three outgroups. The cladistic analysis yielded two most parsimonious trees (tree length 124 steps; consistency index 0.56; retention index 0.86). The evolution of psammophily versus loam-confined life is compared to the cladogram: unexpectedly, psammophily is not an evolutionary innovation that occurred once in a monophyletic group; the evolutionary scenario that parsimoniously fits the phylogeny suggests that psammophily is ancestral to the genus Willemia and reversed twice to loam-confined life. These results demonstrate that habitat generalists can evolve from habitat specialists and therefore that habitat specializations are not necessarily an evolutionary dead end. Many other seemingly specialized characters may be shown to be equally malleable.

  • a review of willemia buddenbrocki group collembola poduromorpha Hypogastruridae with cladistic analysis
    Journal of Natural History, 1998
    Co-Authors: Cyrille A Dhaese, Wanda Maria Weiner
    Abstract:

    The authors describe three new species of Collembola belonging to the genus Willemia, one found in Thailand and New Caledonia, and the other two in Nepal. Redescriptions of W. nadchatrami Yosii, 1959 and W. brevispina Huther, 1962 are proposed. A comparative table of species from the Willemia buddenbrocki-group is given, as well as an identification key to this monophyletic group. A cladistic analysis of this group is performed with Hennig86.

Maria Cleide De ,mendonça - One of the best experts on this subject based on the ideXlab platform.

Penelope Greenslade - One of the best experts on this subject based on the ideXlab platform.

  • the importance of long term surveys on species introductions in maritime antarctica first detection of ceratophysella succinea collembola Hypogastruridae
    Polar Biology, 2019
    Co-Authors: Natalia Enriquez, Penelope Greenslade, Luis R Pertierra, Pablo Tejedo, Javier Benayas, Maria Jose Lucianez
    Abstract:

    Biological invasions are one of the major threats to Antarctic native biodiversity and to ecosystems integrity. Regional environmental change and increasing human activity in Maritime Antarctica facilitates the introduction, establishment and colonisation of an increasing number of non-indigenous species. Systematic monitoring is an essential tool for the early detection of the arrival of non-indigenous arthropods. In this study, we compiled the results of a long-term monitoring effort from 2011 to 2017 to survey non-native collembolan species on Deception Island, a highly visited terrestrial site in South Shetland Islands (Maritime Antarctica). Results include the first record of Ceratophysella succinea (Gisin) (Hypogastruridae) in Antarctica. Moreover, the global dataset indicates that the total number and the list of cumulatively occurrence localities for non-native species observed on the island has increased over this monitoring period. This suggests that repeated monitoring is advisable to characterise the full extent of microarthropod introductions into a high biosecurity risk area and improve the effectiveness of surveillance efforts.

  • biology and key to the australian species of hypogastrura and ceratophysella collembola Hypogastruridae
    Australian Journal of Entomology, 2014
    Co-Authors: Penelope Greenslade, J Ireson, Dariusz J Skarzynski
    Abstract:

    The family Hypogastruridae is represented by nine genera in Australia, three of which: Mesogastrura Bonet, Hypogastrura Bourlet and Ceratophysella Borner, consist only of species that have been probably introduced from Europe within the last 250 years, with the exception of a new species described here. All species in these three genera are typical of, and abundant in, disturbed habitats. The 11 species currently recorded from Australia in Hypogastrura and Ceratophysella are C. communis (Folsom, 1897), C. denticulata (Bagnall, 1941), C. gibbosa (Bagnall, 1940), C. succinea (Gisin, 1949), Hypogastrura assimilis (Krausbauer, 1898), H. distincta (Axelson, 1902), H. manubrialis (Tullberg, 1869), H. purpurescens (Lubbock, 1867, H. vernalis (Carl, 1901) and H. viatica (Tullberg, 1872), and a new species C. pauciseta sp. nov. Ceratophysella communis was misidentified in some published literature as C. engadinensis Gisin, 1949. Although C. communis is confirmed as occurring in Australia, there now seems to be no evidence that C. engadinensis occurs here, and the name H. denticulata may include more than one species. An illustrated dichotomous key and description is given here for all Australian species of Hypogastrura and Ceratophysella, and their distributions and habitats documented. Their value as indicators of disturbed habitats in Australia is discussed. Collembola in general have been shown to have a positive influence on nutrient cycling. It is not known what contribution Hypogastrura and Ceratophysella make to Australian arable and grazing systems in this respect, but it may be considerable because of their abundance.

  • an ancient antarctic endemic genus restored morphological and molecular support for gomphiocephalus hodgsoni collembola Hypogastruridae
    Systematic Entomology, 2011
    Co-Authors: Penelope Greenslade, Mark I Stevens, Giulia Torricelli, Cyrille A Dhaese
    Abstract:

    Gomphiocephalus hodgsoni Carpenter was only the second collembolon† to be described from the Antarctic continent. It was collected first in 1902 from Granite Harbour, southern Victoria Land, Eastern Antarctica, by the British National Antarctic Expedition (1901–1904). Since then several studies have investigated the distribution, ecology, ecophysiology and molecular composition of the species. Despite two morphological redescriptions and an absence of detailed evolutionary phylogenetic studies, the genus Gomphiocephalus was recently reduced to a subgenus of Schoettella Schaffer. Here, we redescribe the species in detail and use morphological and molecular (cytochrome c oxidase subunit I and 28S) data to indicate its generic relationships within Hypogastruridae. Characters of Gomphiocephalus do not conform with those of any extant genus in the family, including Schoettella. In addition, the only Schoettella species described from the southern hemisphere, Schoettella subcorta Salmon, is shown here to belong in the genus Xenylla. Furthermore, molecular data indicates the genus has no close relationship to any other in Poduromorpha, and in particular Hypogastruridae. Therefore, we restore Gomphiocephalus to generic status. Our results reinforce the already recognized high level of endemism in the Antarctic fauna at both species and generic levels, and emphasise the necessity of using both morphological and molecular data in determining the systematics and evolutionary relationships of the fauna.

Mark I Stevens - One of the best experts on this subject based on the ideXlab platform.

  • an ancient antarctic endemic genus restored morphological and molecular support for gomphiocephalus hodgsoni collembola Hypogastruridae
    Systematic Entomology, 2011
    Co-Authors: Penelope Greenslade, Mark I Stevens, Giulia Torricelli, Cyrille A Dhaese
    Abstract:

    Gomphiocephalus hodgsoni Carpenter was only the second collembolon† to be described from the Antarctic continent. It was collected first in 1902 from Granite Harbour, southern Victoria Land, Eastern Antarctica, by the British National Antarctic Expedition (1901–1904). Since then several studies have investigated the distribution, ecology, ecophysiology and molecular composition of the species. Despite two morphological redescriptions and an absence of detailed evolutionary phylogenetic studies, the genus Gomphiocephalus was recently reduced to a subgenus of Schoettella Schaffer. Here, we redescribe the species in detail and use morphological and molecular (cytochrome c oxidase subunit I and 28S) data to indicate its generic relationships within Hypogastruridae. Characters of Gomphiocephalus do not conform with those of any extant genus in the family, including Schoettella. In addition, the only Schoettella species described from the southern hemisphere, Schoettella subcorta Salmon, is shown here to belong in the genus Xenylla. Furthermore, molecular data indicates the genus has no close relationship to any other in Poduromorpha, and in particular Hypogastruridae. Therefore, we restore Gomphiocephalus to generic status. Our results reinforce the already recognized high level of endemism in the Antarctic fauna at both species and generic levels, and emphasise the necessity of using both morphological and molecular data in determining the systematics and evolutionary relationships of the fauna.

  • contrasting levels of mitochondrial dna variability between mites penthalodidae and springtails Hypogastruridae from the trans antarctic mountains suggest long term effects of glaciation and life history on substitution rates and speciation processes
    Soil Biology & Biochemistry, 2006
    Co-Authors: Mark I Stevens, Ian D Hogg
    Abstract:

    Abstract We carried out a comparative study using mtDNA (COI) for two free-living, endemic, terrestrial invertebrate taxa—the springtail Gomphiocephalus hodgsoni (Hypogastruridae) and the mite Stereotydeus mollis (Penthalodidae) collected from sites throughout Victoria Land and the Queen Maud Mountains, Antarctica. Maximum likelihood (ML) analyses revealed low levels of intraspecific substructuring for G. hodgsoni (⩽2% sequence divergence) with groups mostly corresponding to geographic location. Other well-defined (morphological) species within the Hypogastruridae ranged from 15% to 22% sequence divergence relative to G. hodgsoni. In contrast, ML analyses for S. mollis showed considerably higher levels of intraspecific divergence (up to 18% sequence divergence), suggesting the presence of morphologically cryptic species. Other presently described mite species were also readily discernible (14–18% sequence divergence). Within both G. hodgsoni and S. mollis there were three main groups corresponding to: (1) Taylor Valley; (2) Beaufort Island; and (3) Ross Island together with the adjacent continental sites. We suggest that a common pattern of climatic and geological history over long-term glacial habitat fragmentation have determined the similar geographic and haplotype distributions found for both species. However, a large variation in substitution rate, around eight times slower for G. hodgsoni, compared to S. mollis, may be due to their different life history strategies on the Antarctic continent.

Jianzhen Lin - One of the best experts on this subject based on the ideXlab platform.